Fuel-pump for internal-combustion engines.



LETZENMAYER. FUEL PUMP FDH. 'TEBIvTAL GOMBUSTION ENGL'NES.

APPLICATIGH ENDED APR. 1, 19N.

Patented Apn 28, 19M.

www? y 'lil rirrnur OTTO LIETZENMAYER. GF MUNGH, GERMLBTY.

.FUEL-PUR? FR NZLERNLCOMBUSTIQN ENGNES.

i e,connor..

To UZZ y111/1 om, 'it muy conf-cru.

Be it known that L r'ro LmrznNi/mrnn, citizen or' the lhnpiro ol Gernulny, residing nl; Munich, lVing-lon'i of liururin, Germany, hure ini-exited certain new und useful lm nrofcmcnts in lfuellumps for Internallloinlnrstion Engines; und l do hereby dechire the ii'ollmving to be n full, clear, and exact description of the invention, such as Specication of Letters Patent.

will enable others skilled in th nrt to which itnmiertuins to Ineke and use the some.

'lhis invention is; nedivision of an npplication filed by vme Merch yl, 1907, Serial No.

ll'lgl und relates lo fuel pumps for internul combustion motorsI und the sumo has par-v, liculnr reference lo means for automatically j adjusting or regulating the amount of fuel i fed lio the motor, accordingr to the load or, in

fuel supply, or for forcing the fuel foi-wurd to the engine7 or both, is varied accordingr to the speed with which the governor revolves.

My in\f'ention also comprises such further features. combinations of parts, und details of construction ns will be hereinafter de scribed and then rmrticulnrly pointed out in lhe claims.

The druwing :iccompnnying this speciiicntion represents u vertical central section ol u fuel pump embodying my invention.

Referring to the drawing, it will be noted that the fuel pump A is provided with a fuel inlet i und fuel outlet 0, of any usuel. or suitable construction, the said inlet and outlet being governed by the suction valve s, und lthe pressure vulve p, as will he under* stood. The chamber o of the pump communi-entes with the outlet o, through the pressure valve 72, by lhe fuel duct o. The drawing-in und feeding forward of the .liquid fuel is performed by the plungers l? und lj in the manner now to he set forth.

rl`he plunger l), which posses through a suitable stuffing box, as shown, into the chnmher o, isconnected to a crunk c by tlle.

pitmnn o, the sa'id crunk being operated from the internal combustion motor in any usuel or desiredfwuy To the connecting oint. c2, between the pitman c and plunger l?, connected a linlcrod ca whose rulerum v f is connected to the verticnl sliding-part g of the centrifugal governor G, eis-shown.

rlhe counter-plunger P is actuated in partial opposition to the plunger .P by the ,i

followingl arrangement: The lower portion ol the plunger passes through e brocheta2 secured to the body of the pump A end ends in u head p2, between which head and `the bracket a2 is arranged e helical spring p encircling the part of the, plunger which projects below the bracket a2. This lower portion of therplunpger, as shown, is reduced in cross section, and at its upper portion it possesQ through en erm. h which, by nuts h', h2, muy be adjusted on u slide-rod H, seid slide-rod being, for this purpose, threaded at its lower end, ns shown.4 The said sliderod passes loosely through n, projection on, the body of the pump A, as shown, und is connected by n link 'to the link c3. The reduced portion of the plunger F passes loosely through the nrm'z, Suid arm in its upward movement bearing against the shoulder p formed et the beginning 'o' the said reduced portion of the plunger lj. The reduced portion of the plunger P carries below the arm il a stop zu, which, es shown, consists of n, nut whiclumay he udjustedyer- Atically on screw` threads' out in 'the lower porrecoin-eu Annee, loro original application filed March 4, 1907, Serial No. www5. Divided' and this application filed April l,

Serial No. 552,814.A

plunger P to reciprocate with respect to the pump chamber. In its upward movement it causes the ruel to be drawn into the pumpV chamber through the inlet z' and suction valve s. 0n its downward movement it ucts' to force the fuel through the duets a', the valve 79, and the outlet o to the point of combustion, all in the usuel manner. ing the downward movement of the plunger P thelslide rod Il is carried downward by the link o3 which rocks on the fnlcrum f and thereby the arm h moves downwardly, allowing the counter-plunger Il" to be urged downward by the spring 79B acting on Vthe head 722, until the stop p5 strikes the bracket a2. The arm v71,confirming its downward movement, slides "along the lower reduced portion of the plunger P until the downn ward stroke of the slide-rod H is completed. During this motion the plunger l remains stationary and the plunger P moving to ward it, in reducing the s ace in the pump chamber, forces the liqu fuel out. of the Dur l remains stationary, the

V .valve s. If, new,

- of the plunger P H will be lowered same through the duet a and outlet o. When the plunger P has completed its doWn'-streke the continuing movement of the crank e raises the said plunger P, 'but during the first portion of this upward stroke of said plunger P the counter-plunger P arm )t sliding upwardly on its reduced portion until it strikes the shoulder p4 when the arm it, continuing its upward movement, moves the plunger P upward together with the 'plunger P. During the first-.part of the upward motion of the plunger P the saine4 therefore acts as a suction plunger, causing the liquid. fuel to he drawn'v in to the `pump chamber a through the inlet i by Way oi the suetiou there isa change of load or a change in speed of the'machine, the governor G will raise or lower the fulcrum f of the link 03, this-raising or lowering of the fulcrum f shertens or lengthens the stroke for by raising the fulcrum f this raises the slide rod H which will provide that' the arm il, shall actagainst the shoulder p4 for a greater part of a revolation of the crank the stroke of P. when the fulcrum f, the. governor and in this case the slide rod which signifies that the arm will act upon the shoulder p* for a small part of a revolutionof the crank C `Which,therefore shortens the stroke of the plunger P.

What I claim and desire to secure by Let- C and thereby increase The converse 1s true ters Patent is l. In an internal combustion motor, the combination, with a fuel pump having a main plunger, and means for operating the said main plunger, of an auxiliary plunger for said pump, mans for moving said auxis lowered bymeans ofiliary plunger in synehronisn'i with the main plunger, and means controlled by the speed of the engine for varying the amount of such synchronous movement o' the auxiliary 45 plunger.

2. In a fuel pump for internal combustion engines, a pump chamber` a main plunger working therein, an auxiliary plunger, meansfr yieldingly withdrawing the auxiliary plungerfroin the pump chamber, in combination with av stop on said auxiliary plunger for limiting thevdown'ward movement thereof, a stroke regulator meinbei` E acting against a shoulder on said auxiliary l plunger adapted to raise said plunger, l means controlled by the speed of said en`4 i gine forchanging the position of Said stroke regulatin.1 member thereby regulating the'stroke o said auxiliary plunger.

3. 1n a fuel pump for internal combustion engines, a pump chamber, a main plunger working therein, means for operating said main plunger, an auxiliary plunger, means for yieldingly withdrawing said aux- ,iliary plunger from the pump chamber, said auxiliary plunger provided with a shoulder, in combination with-a lever connected with and operated from the engine shaft and ar ranged to strike the 'shoulder during a por- 70 tion of its lmovement to thereby lift the same, means controlled by the speed of the engine `to, regulate the stroke of said auxiliary plunger, a stop for limiting the downward movement of said auxiliary plunger. In testimon f whereof I hereunto aiiix my signature in tie presence of-two Witnesses.

OTTO LIETZENMAYER. Witnesses:

Louis MUuLnnn, Merriman K. HELD. 

